This invention relates to the field of lamp fixtures and devices which deter or prevent the lamp fixture from being inadvertently tipped over and damaged. The invention is particularly directed to lamp fixtures for use at work sites in the construction industry, but it is also applicable to any other kind of lamp which is supported on a stand or other type of upright fixture such as a table lamp, lantern and the like.
The existing lamp fixtures for use at work sites in the construction industry, such as the quartz lamps known to the prior art, are supported on an adjustable elongated shaft which is held upright by a tripod. These prior art lamp fixtures are easily tipped over when accidentally bumped into by a workman, and the quartz lamp is broken requiring expensive replacement.
This problem is solved by the self positioning or self-righting lamp fixture in accordance with the present invention. It provides an elongated supporting structure for the lamp mounted at its upper end which has a hemi-spherical bottom wall bounding a hemi-spherical cavity in which a volume of weighted material or ballast is uniformly dispersed and secured to lower the center of gravity of the fixture as a whole to some point below the equatorial plane through the upper circumferential edge of the hemi-spherical cavity defined by the curvature of the bottom wall. The weight of the uniformly dispersed ballast is determined by whatever is needed to cause the elongated supporting structure with a quartz lamp mounted at its upper end when laid on its side horizontally to right itself and return to the vertical or upright position.
In other words, the uniformly dispersed ballast in the lower part of the hemi-spherical or rounded bottom wall of the supporting structure is of sufficient weight for gravitational forces acting thereon when the structure is tipped or tilted from its upright or vertical position to cause it pivot back to the upright or vertical position, and to also act as a buffer or restraining force against movement away from the upright or vertical position. Thus, when accidentally bumped into by a workman, the lamp fixture in accordance with this invention will initially be tipped away from its upright position but as soon as the workman steps away the gravitational forces acting on the weighted ballast automatically bring the lamp fixture back to its normal upright position.